Spain and Brazil push global action to tax the super-rich and curb inequality

This is the wrong way to look at the issue.

The super-rich don't stay rich by just sitting on their money, they invest it.

These countries should focus on encouraging investment there - by getting rid of bureaucracy and red tape, make it possible to hire across the whole EU a lot easier, without needing separate tax registration in every country, etc.

Lower the barriers to entry wherever possible - no long application processes for developments with endless consultations, no arbitrary minority language or qualification requirements, etc.

Income inequality is a good thing, but there needs to be equal access to education and opportunities and the lowest barriers to entry possible.

Is this not the same trickle down mantra that has been pushed across developed countries for decades and has only widened the gap between rich and poor? In the US, where this line was pursued since the 80s, real wages for most Americans have stagnated while the top 20% have seen their wealth increase astronomically. Merely improving the regulatory and investment climate for a country does not magically benefit most citizens in a society -- thoughtful taxation is one to correct that.